RSpec double/mock instance variable from initializer

Question

I've got a class where in initializer I need to call instance variable from parsed params:

class PrintResults
  include SortResults

  attr_accessor :views_hash

  def initialize(parser)
    @parser = parser
    @views_hash = parser.page_views
  end

I want to test attributes accessors, I tried something below:

RSpec.describe PrintResults do
  subject { described_class.new(views_hash) }

  describe 'attributes accessors' do
    let(:accessors) { double(page_views: { '/that_70s_show' => ['111.111.111.111'] }) }

    it 'should have views hash' do
      subject.views_hash = accessors
      expect(subject.views_hash).to eq(['111.111.111.111'])
    end
  end

but I'm getting an error:

  1) PrintResults attributes accessors should have views hash
     Failure/Error: expect(subject.views_hash).to eq(['111.111.111.111'])

       expected: ["111.111.111.111"]
            got: #<Double (anonymous)>

       (compared using ==)

       Diff:
       @@ -1 +1 @@
       -["111.111.111.111"]
       +#<Double (anonymous)>

spickermann · Accepted Answer · 2020-12-03 19:39:39Z

4

You assign your test double directly to the attribute that is returned instead of using the initialize method.

Instead of

subject { described_class.new(views_hash) }

describe 'attributes accessors' do
  let(:accessors) { double(page_views: { '/that_70s_show' => ['111.111.111.111'] }) }

  it 'should have views hash' do
    subject.views_hash = accessors
    expect(subject.views_hash).to eq(['111.111.111.111'])
  end
end

use

subject { described_class.new(parser) }

describe 'attributes accessors' do
  let(:parser) { double(page_views: { '/that_70s_show' => ['111.111.111.111'] }) }

  it 'should have views hash' do
    expect(subject.views_hash).to eq('/that_70s_show' => ['111.111.111.111'])
  end
end

answered Dec 3, 2020 at 19:39

spickermann

108k9 gold badges115 silver badges147 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

RSpec double/mock instance variable from initializer

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related